Lyric N-Point Matte
The Lyric N-Point Matte lets you draw a closed matte shape with a variable number of points, up to 16. The vertices can be rounded with a variable radius. A separate matte image or clip can be placed within the shape bounds. The shape fill and outline can be separately controlled, allowing both filled and variable-width outline mattes to be constructed.
This mask is used as a compositing mask, to select a feature that is to be composited over another clip, or as a filter mask to perform some correction or stylizing on the selected feature, and it is often used as a garbage matte in conjunction with another matte to limit the areas selected by the second matte. This latter is achieved by using the Alpha Channel Intersection capabilities of all the Lyric Mattes.
The Lyric N-Point Matte filter includes a set of matte and output controls that are common across all Lyric matte filters. For a detailed description of these controls, please see the Matte Common Controls documentation.
For background information on mattes and their uses in Final Cut, please refer to the Lyric Matte Primer.
The Geometry section contains controls that govern the shape & placement of the matte. The number of vertices in the shape is set via the Number of Points slider. On-screen point number labels can be enabled with the Show Point Lables checkbox. These only appear in preview mode in the Canvas and are not present in any rendering or in the matte that is inserted into the clip's alpha-channel.
The vertices of the shape can be positioned using the Point controls that follow. The best way to set up interactive shape creation is to apply the matte to a clip already in the timeline, double-click the clip to bring it into the Viewer window and select the Filter tab. Place the timeline playhead within the clip containing the filter, so that the clip is visible in the Canvas. Now you can select the point controls (by clicking on the circular '+' button) and then click and drag it's position in the Canvas. It may be useful to enable the Show Matte checkbox in the Output section in order to see both the image and the matte together while it is being constructed.
The Fill section contains controls that determine how the shape is filled. If Enable Fill is off, the shape is not filled, if it is on the shape will be filled with white (opaque) or the Fill Image/Clip if one has been dropped onto its clip well. Opacity controls the white-level in the fill, decreasing opacity reduces the fill color down to black through levels of gray, effectively reducing the opacity of the matte. Softness feathers the edges of the matte filling. If a fill clip or image is supplied, it will either be clipped or scaled to fit the shape, depending on the state of the Fit Clip checkbox.
The Frame section contains controls that determine how the shape is outlined. The frame is enabled via Enable Frame and Thickness controls the width of the frame. Opacity and Softness operate as they do for the fills, but only on the frame.
Enabling Rounded Corners applies a rounding to each corner of the shape whose radius is controlled by the Radius slider. Note that since the radius is the same on all corners, the maximum radius that can be applied is determined effectively by the shortest side, as the arcs from each end of that side meet.
The Matte Control and Output sections are common controls that are documented on the Matte Common Controls page.
Remember, you can stack several Lyric Matte filters in a single clip to make a final composite matte by setting their Matte Mixing menu to appropriate values: Add to Existing Alpha will combine selections, Subtract from Existing Alpha will remove some unwanted part of the matte and Intersect with Existing Alpha will make the combining mattes act like garbage mattes for one-another. You can also use the Final Cut crop tool as a final garbage matte; it is applied after all other mattes are applied.